They call me the cory killer

[threnjen]

So what is my deal with cories? I can't keep these fishies, which of COURSE are my favorites, alive at all. (I also can't seem to keep otos alive, but that was its own topic)

My first batch of punctatus cories contracted columnaris brought in by a batch of dwarf cories (confirmed at LFS). Every single cory of both types was wiped out. Fine, that was not my fault. I can deal. (yes I tried to save them, bought hospital tank, medsapalooza, etc etc that is all old and done. columnaris is evil the end.)

Well months later after I have QTed and implemented every other member of my tank. All that's left t add are the cories. I still have sad feelings when I think about them, but hey, what could go wrong?

Bought 8 Julii cories. 2.5 weeks later, I have TWO.
?!?!?!?!?! In this time I've done a few desperate things, including a round of Jungle Fungus Clear (contains Nitrofurazone aka Furan 2) and a double round of anti-parasites. This was a normally cycled QT tank that has been moving healthy QT fish on rotation for weeks. In fact, in addition to this series of cories that are DYING, it also has housed 6 guppy fry that are thriving! So whatever is wrong, it kills my cories but the FRAGILE BABY FISH just keep right on ticking.

I drip acclimated, kept on top of my TDS, WC regularly, etc etc.

The only thing of interesting note is I checked their water from the LFS and it was like... MEGA nitrates. Like off the chart. And the tank they were going in had maybe 2, as at the time it had only a few guppy fry and I did a water change. I could accept if the nitrate shock killed a few but I didn't even have my first death for a week. Since then it has been steady deaths every few days.

I'm also terrified because one of them was getting a bit of a white patch on his head (a dreaded columnaris sore?! It cannot be...). Well he died before it got any bigger, so that was no lead.

I'm starting to think I'm just not meant to have cories.

What might I have done wrong that I am not considering?

 

[rhsoto94]

I'd like to see what advice anyone can offer. I have the same problem with my julii cories all of them seem perfectly healthy until I find one dead randomly. All my other fish are perfectly fine. They seem like a money pit for me because I'm down to two and keep buying more to keep a school. I don't want to buy more but I wanna keep them happy in a school I'm so conflicted haha.

 

[GodFan]

What kind of substrate do you use? Also what do you feed? I assume you know that cories cannot have any salt in there tanks right?
It may be a bad LFS. Especially if rhe trates were that high.

 

[threnjen]

The substrate is a mix of CaribSea Peace River (a non-sharp small gravel) and Torpedo Beach (a smaller sand)
Freshwater Aquarium Substrate: CaribSea Instant Aquarium Tropical Aquarium Substrate

They get Hikari sinking bottom feeder wafers.

Yep, no salt.

I'm unhappy/surprised at the high nitrates. This is a dedicated LFS not a chain store and they are changing tank water every time I am in there! I mean I see a person working on WCes every time I go in! That was an unpleasant surprise to see the nitrates so bad.

 

[threnjen]

I'd like to see what advice anyone can offer. I have the same problem with my julii cories all of them seem perfectly healthy until I find one dead randomly. All my other fish are perfectly fine. They seem like a money pit for me because I'm down to two and keep buying more to keep a school. I don't want to buy more but I wanna keep them happy in a school I'm so conflicted haha.

I know how you feel. Now I have two so I'm like... do I go buy more.. ??

 

[sabrinarichard]

That sucks, I had the same thing happen with shrimp, I gave up a few months ago and was so disappointed because the lasted maybe a few days. But about two weeks ago I don't know what came over me (ok it was my lfs manager offering me a 10$ shrimp half price to encourage me) and he is doing super! I have since gotten cherry shrimps for my fry tank and another success! I believed my tank to be "established" before I honestly don't know what changed, and my stocking is the same.. Actually everything is the same! I really don't get it..

 

[GodFan]

The substrate is a mix of CaribSea Peace River (a non-sharp small gravel) and Torpedo Beach (a smaller sand)
Freshwater Aquarium Substrate: CaribSea Instant Aquarium Tropical Aquarium Substrate

They get Hikari sinking bottom feeder wafers.

Yep, no salt.

I'm unhappy/surprised at the high nitrates. This is a dedicated LFS not a chain store and they are changing tank water every time I am in there! I mean I see a person working on WCes every time I go in! That was an unpleasant surprise to see the nitrates so bad.

Im suspecting bad stock however in order to rule out all possibilities I have a few more questions. What are they being stocked with? Are you feeding any fish in the tank frozen or live food?

 

[Delapool]

Interesting to see what turns up here!

I've just about given up on platies which I think should do just as well as mollies but they don't seem to do well at all.

 

[threnjen]

Im suspecting bad stock however in order to rule out all possibilities I have a few more questions. What are they being stocked with? Are you feeding any fish in the tank frozen or live food?

They are in a 10g QT tank which has had several fish pass through in the last couple months to no ill effect. The only fish in with them at this moment are two adult male guppies and a male fry. There have been up to 4 fry in there at a time but never more than the fry and two adult guppies (no ill end to the other fry, just identified as female and returned to the display). As a note the adult guppies are not "in quarantine" still, I just wanted to separate males/females so I moved them back into the 10g. The guppies get a little pinch of flake, really tiny. Oh and some pond snails and an assassin, which hardly counts. No frozen or live foods. Just the bit of flake and the Hikari bottom feeder pellets.

Tank has a piece of driftwood and several plants. None of these items were in the tank when it housed columnaris-infected fish. The tank was broken down and disinfected after that and all things in the tank were thrown away (substrate, filter media, plants, wood tossed). There have been no sick fish in the tank since then.

 

[Delapool]

Could it be your soft water? Just too much difference to lfs over all and they just fade away?

 

[threnjen]

I actually tested the TDS of the LFS water and my 10g tank water and it was within 5 ppm, I was very impressed. I remember theirs was 111 and mine was just under that.

 

[threnjen]

They are probably using the same water as me anyway, as far as TDS goes. I'm pretty sure they fall under the same watershed. So we definitely shouldn't be crazy different. But it's a good idea. I'll listen to ANY ideas!

 

[GodFan]

Threnjen do you use a water softner at your house? Like well water or something? Water softeners have salt in them. Do the cories barbels seem healthy when you get them? I really think you should try cories fdom somewhere else.

 

[Old Scales]

Thren, I've followed your threads and advice long enough to know you are a good, knowing aquarist that bases your judgments on facts. Your water parameters and substrate are very similar to mine and I've had the same six False Julies for a year now. You even feed them the same way I do. IMO, you're getting weak stock. As suggested, try a different source. I'm perusing through Planet Catfish and some other sites looking for any clue I can find for you. Later, OS.

 

[Brookster123]

Thren, I've followed your threads and advice long enough to know you are a good, knowing aquarist that bases your judgments on facts. Your water parameters and substrate are very similar to mine and I've had the same six False Julies for a year now. You even feed them the same way I do. IMO, you're getting weak stock. As suggested, try a different source. I'm perusing through Planet Catfish and some other sites looking for any clue I can find for you. Later, OS.

+1 it has to be the stock, with your knowledge and dedication I find it rather hard to believe these deaths are in anyway related to anything you're doing or not doing..

 

[Caliban07]

This happened to me also. Ottos and Cories. It could have been a mixture of things that killed mine. I did have columnaris as you know. But it could have been the meds or the out if date fish food that killed them.

I'm not going to buy ottos ever again and as for cories, maybe another year down the road.

I'm just wondering (not sure how LFS systems work or if they're all the same) but most of them look like they're on a shared system with extremely small tanks. My guess is that a few missed water changes here and there would increase the baseline nitrate level each time and just force them to creep up. They'd have to do a 100% water change to remove them all which I'm sure they don't.

 

[GodFan]

This happened to me also. Ottos and Cories. It could have been a mixture of things that killed mine. I did have columnaris as you know. But it could have been the meds or the out if date fish food that killed them.

I'm not going to buy ottos ever again and as for cories, maybe another year down the road.

I'm just wondering (not sure how LFS systems work or if they're all the same) but most of them look like they're on a shared system with extremely small tanks. My guess is that a few missed water changes here and there would increase the baseline nitrate level each time and just force them to creep up. They'd have to do a 100% water change to remove them all which I'm sure they don't.

I wouldnt give up on ottos. They are very hardy once established. Since it appears more than one person is having an issue with just these species it could be some odd factor we are all missing. I say try new stock and ifnit doesnt work then know it is something in your water cories dont like. Cories and ottos both are sensitive to salt. If salt is in your water from the tap you may not even know it.

 

[threnjen]

Godfan, no water softener. Mine is super duper soft (in the correct terminology for fish) right out of the tap. It's usually from 11-18 TDS. Crazy! I actually remineralize just a smidge with Equilibrium so that it's not quite so devoid. I'm going to have a good time of it if I ever do saltwater!

OS & Brookster... you guys are sweet <3 I have lots of "book" knowledge but that doesn't always turn into practical application for me... like right now

Caliban this LFS is all individual tanks, they walk along doing individual WCes on every tank and they all have their own sponge filters.

I'm really just at a loss. I also forgot to mention, the one that got the white patch on his head, he also lost finnage on his right side (what are the side fins called, I forget). He just had a little stub for his right lateral fin. He still got around, but he was very lopsided. It also looked like some of his barbels were eroded. Both of those things were evident before he developed the sore. I wonder if that one was sick and sickened the others. However I do not know his state when I got him. Was he like that or did something happen?? I don't know. I did not notice his problems until a few had died already, I think 2 died before I noticed him. Maybe my big failure was with observation Maybe I should have moved him out on his own.

The only thing I can possibly think of is I stressed them out with too much "interference" or something. I'm kind of a fiddler by nature and maybe I just freaked them out. I did move some plants around in the tank, but it was to give them better hiding spaces, and I only did it once on one day. So I don't mean I constantly had my hands in the tank messing with stuff. I just moved the plants around once to provide them better cover.

One of them died right after a water change. And yes I DEFINITELY used my dechlor. At the time it happened I immediately asked myself that but I remembered 110% adding it in (plus the other fish especially the fry would have had more trouble if I didn't).

I really appreciate you guys. I wish it didn't just make me more at a loss! I like to know why things happen. I'm ok with making mistakes as long as I can resolve them so I'm not doomed to repeat them!!

 

[GodFan]

Godfan, no water softener. Mine is super duper soft (in the correct terminology for fish) right out of the tap. It's usually from 11-18 TDS. Crazy! I actually remineralize just a smidge with Equilibrium so that it's not quite so devoid. I'm going to have a good time of it if I ever do saltwater!

OS & Brookster... you guys are sweet <3 I have lots of "book" knowledge but that doesn't always turn into practical application for me... like right now

Caliban this LFS is all individual tanks, they walk along doing individual WCes on every tank and they all have their own sponge filters.

I'm really just at a loss. I also forgot to mention, the one that got the white patch on his head, he also lost finnage on his right side (what are the side fins called, I forget). He just had a little stub for his right lateral fin. He still got around, but he was very lopsided. It also looked like some of his barbels were eroded. Both of those things were evident before he developed the sore. I wonder if that one was sick and sickened the others. However I do not know his state when I got him. Was he like that or did something happen?? I don't know. I did not notice his problems until a few had died already, I think 2 died before I noticed him. Maybe my big failure was with observation Maybe I should have moved him out on his own.

The only thing I can possibly think of is I stressed them out with too much "interference" or something. I'm kind of a fiddler by nature and maybe I just freaked them out. I did move some plants around in the tank, but it was to give them better hiding spaces, and I only did it once on one day. So I don't mean I constantly had my hands in the tank messing with stuff. I just moved the plants around once to provide them better cover.

One of them died right after a water change. And yes I DEFINITELY used my dechlor. At the time it happened I immediately asked myself that but I remembered 110% adding it in (plus the other fish especially the fry would have had more trouble if I didn't).

I really appreciate you guys. I wish it didn't just make me more at a loss! I like to know why things happen. I'm ok with making mistakes as long as I can resolve them so I'm not doomed to repeat them!!

This is very strange. You have done everything right it sounds like. I had a banjo cat whos fins turned white and eroded away. He had nothing but bone. The he started losing skin and died. Dont kjow why on him either. He was at the top of the tank alot. Are the cories acting odd like being at the top of tbe tank? Also just a thought do you have any plecos or other bottom dwellers?

 

[Caliban07]

The complexity involved with the water chemistry we keep in our aquarium and how it effects each species differently makes it so hard to pin it down to a specific reason.

What substrate do the LFS keep their cories in?

We don't know how much our fish are moved around before they finally reach our waters and what chemicals are added to the bags etc to make them last. I read a really interesting article on this some time ago and the things a fish is subjected to to get them to the LFS are not good.

Thing is though Jen. I'm not saying your LFS do not maintain there tanks correctly but if for example the schedule is changed or skipped or something comes up or someone phones in sick etc nitrates can quickly build up. Especially in smaller tanks.

If a tank has 20ppm nitrates by the end of week 1 and a 50% water change is carried out it leaves 10ppm if for some reason that tank misses a clean or it takes longer to get to before the next clean it could have 30ppm and a 50% change now means the tank has 15ppm. I know you understand what I'm getting at here.